Concentrate on developing prostaglandin analogs which regulate the luteal function so as to control human fertility. Synthesize in 100 mg quantities (+)-15-epi-12-fluoroPGF2a (1) and optically pure 12-hydroxyPGF2a (4) for biological evaluation in the monkey. Also synthesize in optically pure form for the first time the following prostaglandin analogs which will be evaluated for antifertility activity in the hamster: 12-fluoro-13,14-dihydroPGF2a (2), E-13,14-12,14-difluoroPGF2a (3), 12-hydroxy-13,14-dihydroPGF2a (5), and the three 12-fluoro analogs 6, 7, and 8. In addition, the six corresponding C(15) epimeric compounds 2', 3', 5', 6', 7', and 8', will be synthesized. Preliminary testing on analogs (+)-1 and (+,-)-4 has already been completed. All other analogs will be examined for pregnancy interruption in the hamster and smooth muscle stimulating effects on gerbil colon and hamster uterine strips.